Traditional pointing devices for controlling the position of a cursor on a display include arrow keys, function keys, mice, track balls, joysticks, j-keys, touch screens, light pens, tablets and other similar devices for controlling cursor movement and selecting items or functions on the display. Although these traditional pointing devices are generally satisfactory for many applications, in environments where the pointing device must operate in a limited workspace and fit within the form factor of an electronic device, such as a laptop computer, personal digital assistant (PDA), wireline or wireless telephone, video game or other similar electronic device, traditional pointing devices do not provide sufficient cursor control speed or accuracy.
Recently, puck-type pointing devices have been introduced to the laptop and hand held device industries to overcome many of the limitations of earlier pointing devices. Puck-type pointing devices are compact puck-shaped devices that may be manipulated by a user's finger to move within a puck field of motion. The position of the puck in the puck field of motion is sensed using a variety of electrical, electromagnetic and optical techniques, and the position of the puck is mapped to a cursor position on a display. Examples of puck-type pointing devices are described in U.S. Pat. No. 6,084,570 to Milroy, entitled “Compact Cursor Controller Structure For Use With Laptop, Notebook and Hand-Held Computers and Keyboards,” U.S. Pat. No. 5,771,037 to Jackson, entitled “Computer Display Cursor Controller,” U.S. Pat. No. 6,278,440 to Katsurahira et al., entitled “Coordinate Input Apparatus and Position-Pointing Device,” and U.S. patent application Ser. No. 10/723,957 to Harley et al., entitled “Compact Pointing Device.”
Although existing puck-type pointing devices are faster and more accurate than other traditional pointing devices in the portable electronic device industry, effective operation of a puck-type pointing device requires visual feedback to the user to locate menu items and other software-defined keys on the display. However, for some applications, it is desirable to locate display items without looking at the display. For example, when driving, a user may prefer to select a menu item or dial numbers on a software keypad using only tactile feedback in order to maintain visual contact with the road.
In addition, most puck-type pointing devices include one or more buttons or other type of selection mechanism for selecting items on the display. However, during a “clicking event” in which item selection depends on positioning the cursor over the item on the display and simultaneously clicking or tapping the button or other selection mechanism, many users have found that is difficult to maintain the position of the puck over the item while clicking, thereby resulting in incorrect item selections.